It really depends on the topic and who the forumite character
they are replying to. If you see deeper, there is a hidden message
behind every joker reply and behind every intent of the replies.
The hidden message often relays to what the replying character felt
and how serious he/she/it views the topic.
Normally its a masquerade to either divert topic or to hide the
real intent and severity of the issue discussed at hand (to keep it
in check lest it blows out of proportion) although there are real
joker replies purely for the sake of joking.
So... it depends on what you read, what angle you are reading from
and how serious you are in dealing with it.